Method of and apparatus for heat interchange



Sept. 15, 1931. H. H. DOW ET AL 1323,0133

' METHOD OF AND APPARATUS'FOR HEAT INTERCHANGE I 7 Filed Feb. 20, 1926 3 Sheets-Sheet l INVENTFORS I An els/3? P 15, 1931- H. H. DOW ET AL I 1,823,033

METHCFDD or AND APPARATUS FOR HEAT INTERCHANGE I Filed Feb. 20, 1925 v s SheetS- -Sheet 2 I INVENTORQ 1 fler-derfffflow and ATT6RNEY5 v Sept. 15, 1931. H. H. DOW ET AL METHOD OF AND APPARATUS FOR HEAT INTERCHANGE Filed Feb. 20, 1926 3 Sheets-Sheet .3

' I, 'IYNVENTORS,"

11w ATTORNEY nation of one medium with Patented Sept. 15, 1.931 p UNITED S -res PATENT OFFICE EB'J. n. DOW AND our H. cANNoN, or MIDLAND, iirIcnieAN. ASSIGNORS, 13v MESNE ASSIGNMENTS, TO IR PREEEATER CORPORATION, or-NEw YORK, N. Y., A

'coBronA'noN-or Nnw Year;

METHOD OF AND APPARATUS FOR HEAT INTERCHANGE Application filed February 20,1926. Serial No. 89,616.

Thisinvention relating, as indicated, to heat interchange, hasmore particular reference to interchange between media which may in part carry suspended matter, or

a 5 which may be of more or less corrosive character. Heretofore it has-been a matter of considerable difliculty to'keep passages clear where a medium leavingdeposited matter was employed, also more or less contamithe other has been usual.

An arrangement by which clogging and contamination may be prevented is accordingly highly desirable. To the accomplishment of the foregoing and related ends, the invention, then, consists of the means and procedure hereinafter fully described, and particularly pointed out .in the claims, the annexed drawings and the following description setting forth in detail certain features embodying the invention, such disclosed features constituting, however, but one of various forms in which the principle of the invention may be used.

In said annexed drawings: a

Fig. 1 is a central vertical section through a construction embodying the present improvements; Fig. 2 is a section taken on the plane indicated by the line 11-11, Fig. 1;

Fig. 3 is a section taken on the plane indicated by the line III-III, Fig. 1; Fig; 4 is a transverse sectional view taken in part through the filling near the base of the tower and in part atlowerplanes above and below the grating; Fig. 5 is a sectional detail of the filling near the top of the tower, and Figs.

6, 7 are perspective views of the lower valve showing the flow channels.

Ihe reference numeral 2 in the drawings designates an outer shell, and centrally theree within is an inner shell 3. The precise form and detail of these may vary somewhat but the arrangement as shown is generally most satisfactory. Radial partitions 4 between these shells divide the space into compartments, preferably an odd number. At the upper and lower ends of the inner shell are valve cages 5 and 6 which have openings laterally. Mounted in the valve cages are retary valves 7 and which comprise respective base plates 7a and 8a with a wall 7 b or 86 of more or less cylindrical shape and providing port openings at one side. A segmental wall or. 80, as the case may be, is supported in spaced out relation to the inner Wall 7 b or 8?) and is proportioned to just close 4 o a port leading to the compartments, while extensions 7 e or 8e, as the case may be for the respective valves, are provided which again are proportioned to just close a port which they may be placed squarely. over. It is thus seen that the valves establish channels leading to the ports, the channels being suchthat in the particular form illustrated in Fig. 2, two compartments will be in communication with the valve opening A and two compartments with the valve opening B while the'remaining compartments will be in communication with the general valve channel C. It is desirable that a larger number of compartments be opened to the channel C than to the combined passages A and B. The valves are both mounted on a common shaft 9 which and the duct 13, an outlet for exhaust gases,

for example stack gases. A shaft 14 carrying fans 15 and driven by suitable means, for instance, a pulley 16, provides forced.

draft where necessary. At the o posite end of the apparatus, an inlet duct 1 allows of communication with a source of 'hot gases and ducts 18 and 19 are arranged for the discharge of heated air or whatever other me dium has been usedfor taking up heat from the hotter gas.

In order to increase the conducting surface and provide tortuous channels through the compartments, a packing" or filling, preferably of iron rings or cylindrical sections 'is arranged with the units in staggered order.

The units 20 as placed in the lower portions of the compartments are of different form or at least thicker wall than the units 21 ,which are' used for the upper portions of for the gases to be introduced.

In operation, the shaft 9 is put in rotation and a hot gas, for instance, combustion gases from a furnace is admitted by duct 17 and is diverted through the compartments in succession.- At the same time a cool gas whose temperature is to be raised, for instance, air, is admitted by duct 12 at the opposite end of the apparatus and is passed through the compartments successively after the flow of hot gas. The velocity of the air is such by virtue of the relative sizes. of cross sectional area provided for flow or-by the driving means for forcing it that the flow of air downward is much more energetic than the flow of the combustion gases upwardly. It thus results that the blast of air through any given compartment is such as to dislodge and blow out settled matter such as soot, ashes or the like and the passages are thus kept measurably clear. The valves .being in continuous rotation, the air in passing down isdiverted successively in two streams through the channels A and B. The blast through channel A sweeps out residual gas which may have been left from the combustion gas preceding in flow through the compartment and this contaminated air finds outlet ultimately through conduit 18 from whence it may be disposed of as desired. The successive sweep of air through channel B after passing through the compartments proceeds thence ultimately'through conduit 19 and since the compartments have been swept clear of residual hot gas by reason of the first blast of air, the second blast is uncontaminated and may be used for any purpose re uiring an uncontaminated supply. It will e noticed that-the valve element 70 or 80 as the case may be bein intermediate between the channels and serves to cut off in its revolution one compartment intermediate the two streams of air and intermingling is thus prevented. By reason of the greater thlckness of the units 20 as employed at the base of the tower, any corrosion which may result from acid-in the heating medium is provided for, since such corrosion as might occur would be more intensivev nearest the point of inlet of the hot gases and the strength of the units of=the filling will still be suflicient to support the superincumbent mass even after allowing for corrosion to qulte a considerable extent. A thinner wall type of unit is suflicient above since the amount of corrosion is much less in this region.

Other modes of applying the principle ofour invention may be employed instead of the one explained, change being made as regards the mechanism herein disclosed, provided the means stated by any of the followingcla-ims 011' thedequivalent of such stated means he emp e therefore particularly point out and distinctly claim as our invention 2-.

1. In a method of heat exchange, the steps of communicating regenerative material with heating'fluid, cuttin off said communication, communicating said regenerative material with scavenging fluid, cutting ofl" said scavenging fluid, communicating. said regenerative material with fluid to be heated, and cutting ofl'said fluid to be heated.

2. In a method of heat exchange, the steps of successively communicating .regenerative material with sup lies of heating fluid, scavening fluid, an'd uid to be heated, and cutting ofl' communication" of the regenerative material with the scavenging fluid prior to communication'with'the fluid to be heated.

3. In a heat'exchan er, a plurality of compartments, heat absor ing material disposed therein, means for supplying a fluid medium of one temperature, and a second fluid medium of another temperature to said compartments, and for dischargin the same from said compartments, means for dividing the flow of the second medium through each compartment in two separate successive stages, valves for controlling the flow of said media through said compartments, and means for operating said valves to successively open and close each compartment to the flow of said first medium and to the flow of each stage of the second medium.

4. In aheat exchanger, a chamber containing regenerative material, means for supplying heating fluid to said chamber, means for supplying scavenging fluid to said chamber,

means for supplying fluid to be heated to said chamber, valve means for controlling the supply of said fluids to said chamber, and means for operating said valve means to successively su ply said fluids to said chamber and to cut 0 the supply of scavenging fluid prior to the suppliy of fluid to be heated thereto.

5. n a heat exchanger, a chamber containing regenerative material, inlett means for supplying heating fluid, scavenging fluid, and fluid to be heated to said chamber, said means includingvalves for independently controlling the flow of each of said fluids into said chamber, means for operating said valves to HERBERT H. DOW.

GUY H. CANNON. 

